Rev. 1.10
42
November 26, 2019
Rev. 1.10
43
November 26, 2019
HT68FB240
USB Low Speed Flash MCU
NORMAL Mode to SLOW Mode Switching
When running in the NORMAL Mode, which uses the high speed system oscillator, and therefore
consumes more power, the system clock can switch to run in the SLOW Mode by set the HLCLK bit
to "0" and set the CKS2~CKS0 bits to "000" or "001" in the SMOD register. This will then use the
low speed system oscillator which will consume less power. Users may decide to do this for certain
operations which do not require high performance and can subsequently reduce power consumption.
The SLOW Mode is sourced from the LIRC oscillators and therefore requires these oscillators to be
stable before full mode switching occurs. This is monitored using the LTO bit in the SMOD register.